arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2010.04417astro-ph.GA
收藏

外观变化的活动星系核:action中超大质量黑洞的密近双星

Changing-look active galactic nuclei: close binaries of supermassive black holes in action

Jian-Min Wang, Edi Bon

摘要:

变貌活动星系核(CL-AGN)作为一种新的星系核亚群,其时间尺度与吸积盘模型之间存在着很大的矛盾,对活动星系核的一些基本物理性质提出了挑战。在这封信{ \textit{} }中,我们证明了极端的情况:具有高偏心率的超大质量黑洞(CB-SMBH)的近双星能够通过一个轨道触发CL跃迁。在这种情况下,双黑洞建立自己的迷你磁盘剥离气体的内边缘的环联盘在apastron阶段,之后,他们与磁盘潮汐相互作用在近星相有效地交换角动量在一个轨道周期。对于逆轨道旋转的迷你盘,潮汐扭矩迅速挤压迷你盘的潮汐部分到一个小得多的半径,这迅速导致更高的吸积和短耀斑之前的磁盘下降到2型活动星系核。逆旋转的迷你盘从双星获得角动量并向外旋转,这导致从类型1到类型2的快速关闭。开启发生在离星阶段。CB-SMBH控制周期之间的转换类型-1和类型-2的轨道周期,但允许不同的性质在CL-AGN光变曲线。

英文摘要:

Changing-look active galactic nuclei (CL-AGNs) as a new subpopulation challenge some fundamental physics of AGNs because the timescales of the phenomenon can hardly be reconciled with accretion disk models. In this Letter{\textit{}}, we demonstrate the extreme case: close binaries of supermassive black holes (CB-SMBHs) with high eccentricities are able to trigger the CL transition through one orbit. In this scenario, binary black holes build up their own mini-disks by peeling gas off the inner edges of the circumbinary disk during the apastron phase, after which they tidally interact with the disks during the periastron phase to efficiently exchange angular momentum within one orbital period. For mini-disks rotating retrograde to the orbit, the tidal torque rapidly squeezes the tidal parts of the mini-disks into a much smaller radius, which rapidly results in higher accretion and short flares before the disks decline into type-2 AGNs. Prograde-rotation mini-disks gain angular momentum from the binary and rotate outward, which causes a rapid turn-off from type-1 to type-2. Turn-on occurs around the apastron phase. CB-SMBHs control cycle transitions between type-1 and type-2 with orbital periods but allow diverse properties in CL-AGN light curves.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑